TGFbeta Blockade in MART TCR-Engineered T Cell Melanoma Immunotherapy in Man

描述（由申请人提供）：对癌症免疫学的进一步理解使临床翻译取得了重大进展。在转移性黑色素瘤患者中使用T细胞受体（TCR）工程化T淋巴细胞的过继细胞转移治疗，已在其他组和我们组观察到显著的临床反应。这些反应率超过50%，然而，根据我们的经验，患者最终会复发。我们假设这些高度活化的细胞毒性T淋巴细胞在进入免疫抑制性肿瘤微环境时，随着时间的推移失去了其效应功能。肿瘤分泌的TGF β是肿瘤微环境免疫抑制特性的主要贡献者。我们假设，将显性负性TGF β受体II（dnTGF β RII）整合到MART-1 TCR逆转录病毒载体中用于扩增患者T淋巴细胞将使这些细胞对TGF β不敏感，从而增强其在黑色素瘤肿瘤微环境中的效应功能。我们建议在转移性黑色素瘤患者的临床研究中检验这一假设，其中两个群体的MART-1 TCR转基因T细胞共输注：一个群体用MART-1 TCR逆转录病毒转导，另一个群体用相同的TCR和dnTGF β RII转导。第一种载体（GMP级）已在生产中，第二种载体已进行临床前试验，将在印第安纳州大学国家病毒生产设施（IU VPF）生产。这两个工程化T细胞群将在淋巴细胞清除预处理方案后重新引入患者体内。过继转移的细胞将通过全身施用白细胞介素-2和MART-126-35肽脉冲的树突状细胞疫苗在体内得到支持。在这项I期临床试验中，主要终点是安全性和可行性;次要终点是研究两种转基因细胞群体的差异持久性，并分析其关键免疫学特征;第三终点将是临床应答。我们的具体目标是：1）在I期临床试验中评估MART-1 TCR/dnTGF β R Ⅱ工程化T细胞过继转移在转移性黑色素瘤患者中的安全性、持久性和临床反应。2)评价与临床应答程度相关的关键免疫学终点。我们将在规定的时间点收集并分析活检组织中的外周血和肿瘤浸润淋巴细胞的数量、免疫表型和功能测定。我们在加州大学洛杉矶分校的研究小组拥有MART-1 TCR临床试验经验，已经了解到一个关键问题是缺乏长期特异性T细胞的持久性和功能。本提案将直接解决这一问题，目标是实现持续的临床反应。

DESCRIPTION (provided by applicant): An improved understanding of cancer immunology has allowed significant advances in clinical translation. Dramatic clinical responses have been observed by other groups and ours with adoptive cell transfer therapy using T cell receptor (TCR)-engineered T lymphocytes in patients with metastatic melanoma. These response rates exceed 50%, however, in our experience, patients eventually relapse. We hypothesize that these highly activated and cytotoxic T lymphocytes, when entering an immunosuppressive tumor microenvironment, lose their effector function over time. Tumor secreted TGF� is a major contributor to the immunosuppressive properties of the tumor microenvironment. We hypothesize that incorporating a dominant-negative TGF� receptor II (dnTGF�RII) into the MART-1 TCR retroviral vector used to transduce patient T lymphocytes will render these cells insensitive to TGF�, resulting in an enhancement of their effector function in the melanoma tumor microenvironment. We propose to test this hypothesis in a clinical investigation of patients with metastatic melanoma in which two populations of MART-1 TCR transgenic T cells are co-infused: one population retrovirally transduced with MART-1 TCR and the other population transduced with the same TCR and the dnTGF�RII. The first vector (GMP-grade) is in hand, and the second vector, already pre-clinically tested, will be manufactured at the Indiana University National Viral Production Facility (IU VPF). These two populations of engineered T cells will be reintroduced into the patient after a lymphodepleting conditioning regimen. The adoptively transferred cells will be supported in vivo by systemic administration of interleukin-2 and MART-126-35 peptide-pulsed dendritic cell vaccines. In this phase I clinical trial, the primary end-points are safety and feasibility; the secondary end-points are the study of differential persistence of the two transgenic cell populations, and the analysis of their key immunological signatures; and the tertiary end point will be clinical response. Our specific aims are: 1) To evaluate, in a phase I trial, the safety, persistence and clinical response of adoptive transfer of MART-1 TCR/dnTGF�RII engineered T cells in metastatic melanoma patients. 2) To evaluate key immunological end-points that correlate with the degree of clinical responses. We will collect, at defined time points, and analyze peripheral blood and tumor infiltrating lymphocytes from biopsies for number, immunophenotyping, and functional assays. Our group at UCLA, with a MART-1 TCR clinical trial experience, has learned that a critical issue is the lack of long-term specific T cell persistence and function. This present proposal will directly address this problem with the goal of achieving sustained clinical responses.